1. Field
The following description relates to a technology for routing in a node device of a name based network system.
2. Description of Related Art
In a network routing technology, such as a content centric network/named data network (CCN/NDN), it is necessary to know of a target place to retransmit a response message, which respond to a request message when the response message is returned to be processed. In a name based networking, such as CCN/NDN, the request message may also be referred to as a request, an interest, or a data request. Also, the response message may be called a response or data.
A pending interest table (PIT) refers to a table that stores a list of received request messages. That is, when a request message is received, a corresponding node device records a traffic path along with information on the request message in the PIT. Upon return of a corresponding response message, the corresponding node device retransmits the corresponding response message to the traffic path of the request message stored in the PIT.
However, the PIT may be a target of a distributed denial of service (DDoS) attack. That is, when a quantity of request messages received exceeds the capacity of the PIT of the node device, the node device has to delete part of the recorded information or discard newly received request messages. Regardless of whether to delete recorded information or discarding newly received request messages, the DDoS attack will eventually be successful because the node device is hindered from normally processing the request messages.
A general Internet protocol (IP) router does not require management of a traffic history. Therefore, a DDos attack scenario, as described above, is not applicable to the IP router. However, in networks, such as the CCN/NDN, where devices are not identified, the PIT functions as essential information for the networking. Thus, the node device corresponding to the router in the name based network system is vulnerable to the DDos attack.